Fruit of a wild cucumber (Echinocystis lobata, Cucurbitaceae), photographed 10/23/2011 near Blissfield Michigan.

Last October I wrote about some wild cucumbers (Echinocystis lobata, Cucurbitaceae) that I found here in a southeast Michigan floodplain forest.  This past October I found them again in the same place, and took advantage of better lighting to get some better pictures of the fruit.  In the photo above the one on the left was the least mature.  It was a fully-developed, green spiny fruit, but hadn’t yet opened.  The one in the lower right was farther along.  You can see how the bottom peeled open to eject the seeds.  The one in the upper right was farther along still.  It had finished releasing its seeds and had turned brown.

Fruit of a wild cucumber (Echinocystis lobata, Cucurbitaceae), photographed 10/23/2011 near Blissfield Michigan.

This photo is a better close-up of a mature, unopened fruit.  These plants grow across most of North America, and if you happen to stumble across one in the autumn they really get your attention. Even in the summer before they fruit, you can recognize them by their somewhat distinct leaves and twining, viney growth.

Parasitoid wasps (Hymenoptera: Ichneumonidae: Tersilochinae) on goldenrod (Solidago sp., Asteraceae) photographed 11/02/2011 near Clayton Michigan.

This late into autumn most goldenrods (Solidago sp., Asteraceae) have dried up and gone to seed.  Last week, however, I found a few small plants in a meadow that still had handfuls of bright yellow nectar-laden flowers.  Upon closer inspection I realized I wasn’t the only one to take notice; the flowers were covered with dozens of these tiny parasitoid wasps (Hymenoptera: Ichneumonidae: Tersilochinae).

Parasitoid wasps (Hymenoptera: Ichneumonidae: Tersilochinae) on goldenrod (Solidago sp., Asteraceae) photographed 11/02/2011 near Clayton Michigan.

With winter fast approaching, it seemed unsurprising that so many of these wasps were crowding around some of the last few sources of nectar.  The individuals shown here spent most of their time with their faces buried in the flowers, lapping up the sugary food.  They emerged only briefly to move from one flower to the next.

Parasitoid wasps (Hymenoptera: Ichneumonidae: Tersilochinae) on goldenrod (Solidago sp., Asteraceae) photographed 11/02/2011 near Clayton Michigan.

Although adults of this subfamily feed on nectar, the larvae are internal parasitoids, predominantly of beetles (Triplehorn and Johnson 2005).   A female uses her long, slender ovipositor to lay an egg inside an active host insect. The egg hatches, the larva feeds on the host’s insides, and then eventually emerges as an adult, killing the host.  Some species of these wasps target beetles that are pests of crops and trees.  Tersilochus conotracheli is a parasitoid of the plum curculio (Coleoptera:  Curculionidae:  Conotrachelus nenuphar), a significant pest of fruit trees (Triplehorn and Johnson 2005).

Literature cited:

Triplehorn, C.A. and N.F. Johnson.  2005.  Borror and DeLong’s Introduction to the Study of Insects.  Seventh Edition.  Thomson Brooks/Cole, Belmont, CA.

Giant ironweed (Vernonia gigantea, Asteraceae) photographed 10/23/2011 in a floodplain forest near Blissfield Michigan.

In the summer when giant ironweed (Vernonia gigantea, Asteraceae) is full of healthy nectar-laden blossoms, I’ve found it visited by silver-spotted skippers, cabbage whites, and other pollinating butterflies, bees, and wasps.  Now that we’re well into autumn, the dried, dead plants still host other insects.

Giant ironweed (Vernonia gigantea, Asteraceae) infested with an unknown gall-making insect. Photographed 10/23/2011 in a floodplain forest near Blissfield Michigan.

While out in a nearby floodplain forest here in southeast Michigan, I noticed a number of galls along the leaf midveins.  Naturally I split some open to find out what insect was responsible.

Unknown gall-making insect larva in a giant ironweed (Vernonia gigantea, Asteraceae). Photographed 10/23/2011 in a floodplain forest near Blissfield Michigan.

I found the larvae of some unknown insect in the middle of the galls.  I’ve made some effort searching the literature on leaf galls, but I have yet to identify this insect.  At this point I suspect it’s a fly (order Diptera) and possibly a gall midge (family Cecidomyiidae).

Sulfur cinquefoil (Potentilla recta, Rosaceae) photographed 10/23/2011 near Blissfield Michigan.

Introduced to North America from Eurasia, sulfur cinquefoil (Potentilla recta, Rosaceae) is an easy-to-identify member of the rose family.  It tends to grow in disturbed places, features palmately-compound leaves of five or (more commonly) seven toothy leaflets, has sulfur-colored flowers with five notched petals, and is generally quite hairy (Brandenburg 2010).

Sulfur cinquefoil (Potentilla recta, Rosaceae) photographed 10/23/2011 near Blissfield Michigan.

The distinct combination of characteristics make this often weedy plant stick out like a sore thumb.  I sometimes see it growing around driveways, buildings, and near field and forest margins. Although there are more well-behaved native cinquefoils, this more aggressive species is listed as a noxious weed in at least five states.

Literature cited:

Brandenburg, D.M.  2010.  National Wildlife Federation Field Guide to Wildflowers of North America.  Andrew Stewart Publishing, Inc., New York, NY.

Differential grasshopper (Orthoptera: Acrididae: Melanoplus differentialis) photographed 10/23/2011 near Blissfield Michigan.

After writing about differential grasshoppers (Orthoptera: Acrididae: Melanoplus differentialis) a few weeks ago, last week I noticed scores of them in a nearby soybean field.  I decided to get a closer look at one of them, and it responded by puking black fluid all over my fingers.  The fluid reminded me of used motor oil, and is apparently a defensive mechanism to deter predators.

Common garter snake (Squamata: Colubridae: Thamnophis sirtalis) photographed 11/02/2011 near Clayton Michigan.

I often come across common garter snakes (Squamata:  Colubridae:  Thamnophis sirtalis) here in southeast Michigan.  Today I was intrigued, however, by this particularly tiny individual.  I stuck a quarter next to his head for scale, and that seemed to arouse his suspicion as he cast a wary eye and flicked his tongue inquisitively.

Common garter snake (Squamata: Colubridae: Thamnophis sirtalis) photographed 11/02/2011 near Clayton Michigan.

These snakes breed in the spring and bear live young in the late summer, so this little guy must have been a juvenile.  He was only about 20 cm (7.9 inches) long, but full-grown adults reach 46 to 137 cm (18 to 54 inches) (Zimmerman 2002).

Common garter snake (Squamata: Colubridae: Thamnophis sirtalis) photographed 11/02/2011 near Clayton Michigan.

Although they usually have three bright yellow stripes running down their length, common garters are highly variable in coloration (Zimmerman 2002).  This snake exhibited a particularly drab, brown-tan coloration.  The typically bright stripes were a dull orange color on this individual.

This reptile was taking advantage of the early autumn sun heating some shale walkway stones for warmth.  With winter right around the corner, he was probably also looking for a warm cozy spot to overwinter.

Literature cited:

Zimmerman, R. 2002. Thamnophis sirtalis.  Animal Diversity Web.  University of Michigan Museum of Zoology.

Tarnished plant bug (Hemiptera: Miridae: Lygus lineolaris) photographed 10/30/2011 near Blissfield Michigan.

The plant bugs are the largest family of all the true bugs (Triplehorn and Johnson 2005).  Among the nearly 2000 North American species, one of the most common is the tarnished plant bug (Hemiptera: Miridae: Lygus lineolaris).  Highly successful as a generalist herbivore, these bugs are known to feed on the sap from over half the cultivated plant species in the United States (Capinera 2001).  It’s often a serious pest of commercial legumes, vegetables, and flowers (Triplehorn and Johnson 2005).

Tarnished plant bug (Hemiptera: Miridae: Lygus lineolaris) photographed 10/30/2011 near Blissfield Michigan.

I found this individual in a local greenhouse, basking in the warmth from the early autumn sun.  The greenhouse hosted various flower and vegetable plants earlier in the year.  In close proximity were both crop plants (especially soybeans) and a wide variety of trees in a mesic hardwood forest.  I can only imagine the smorgasbord this pest enjoyed throughout the year.  With winter fast approaching, this adult was probably looking for a comfortable spot to overwinter.

Literature cited:

Capinera, J.L.  2001.  Handbook of Vegetable Pests.  Academic Press, San Diego, CA.

Triplehorn, C.A. and N.F. Johnson.  2005.  Borror and DeLong’s Introduction to the Study of Insects.  Seventh Edition.  Thomson Brooks/Cole, Belmont, CA.

Northern red oak (Quercus rubra, Fagaceae) photographed 10/30/2011 near Blissfield Michigan.

I first wrote about northern red oak (Quercus rubra, Fagaceae) back in July when these trees were lush and green.  Now that we’re well into autumn, they’re no less impressive.  As with most oaks and beeches, these deciduous trees exhibit a characteristic known as marcescence:  they retain their leaves through the winter.

Northern red oak (Quercus rubra, Fagaceae) photographed 10/30/2011 near Blissfield Michigan.

While most species of maples have by now lost their brilliantly-colored leaves, oaks and beeches remain as some of the few sources of fall color here in southeast Michigan.

Green stink bug nymph (Hemiptera: Pentatomidae: Chinavia hilaris) photographed 10/30/2011 near Blissfield Michigan.

A week ago I found an adult green stink bug (Hemiptera: Pentatomidae: Chinavia hilaris) in a floodplain forest here in southeast Michigan.  Two days ago I found a fifth-instar nymph in a greenhouse not far from that forest.

Green stink bug nymph (Hemiptera: Pentatomidae: Chinavia hilaris) photographed 10/30/2011 near Blissfield Michigan.

Most people are probably familiar with holometabolous insects like bees, butterflies, and flies that hatch as larvae, pupate, and emerge as radically different adults.  Unlike those insects, these true bugs are hemimetabolous and go through several nymphal stages called instars.  When the young hatch (first instar) they somewhat resemble the adults.  Instead of pupating they molt several times into subsequent instars, becoming more adult-like each time.

Green stink bug nymph (Hemiptera: Pentatomidae: Chinavia hilaris) photographed 10/30/2011 near Blissfield Michigan.

Even though the nymph shown here was a fifth instar and only one molt away from being an adult, it still exhibited some rather distinct coloration.  While adults are almost solid green, this nymph had patterns of black, orange, yellow, white, and green.  Such vivid color patterns are common in stink bug nymphs (and many adults).

Green stink bug nymph (Hemiptera: Pentatomidae: Chinavia hilaris) photographed 10/30/2011 near Blissfield Michigan.

This was a cute little guy, even though he released defensive fluid on my fingers.  Unlike many stink bugs, however, the odor didn’t seem too potent.

Hairy vetch (Vicia villosa, Fabaceae) photographed 10/30/2011 near Blissfield Michigan.

After several freezes here in southeast Michigan, today I was surprised to find a plant that was not only still very green, but still flowering.  Its cold tolerance has earned it the name winter vetch, but it’s more commonly known as hairy vetch (Vicia villosa, Fabaceae).

Hairy vetch (Vicia villosa, Fabaceae) photographed 10/30/2011 near Blissfield Michigan.

Hairy vetch gets its name from the densely pubescent compound leaves and stems.  Above you can see that the leaflets are covered in white hairs.  Each leaf is terminated by tendrils that the plant uses to trail and climb over other plants.  These tendrils are visible in the first photo above.

Hairy vetch (Vicia villosa, Fabaceae) photographed 10/30/2011 near Blissfield Michigan.

Introduced and naturalized in North America from Europe, hairy vetch has a number of agricultural applications.  Like other members of the bean family, it’s particularly adept at fixing nitrogen and making it available for subsequent plants.  For this reason it’s often used in rotation as a natural fertilizer for organically-grown crops (Owsley 2011).  Hairy vetch is also valuable as a winter groundcover to prevent erosion, a forage crop for livestock, and as a host plant for beneficial insects (Owsley 2011).

Despite its usefulness, hairy vetch can be invasive.  Left uncontrolled, it can persist and spread (Owsley 2011).  I found these plants near a barn on a farm, and I suspect they were introduced in a mix of hay seed that was sown nearby.  They’ve now escaped the field itself and have spread into surrounding areas.

Literature cited:

Owsley, M. 2011. Plant fact sheet for Hairy Vetch (Vicia villosa). USDA-Natural Resources Conservation Service, USDA NRCS. Americus, GA 31709.